As the famous trouble finder, here is my modest contribution to DOSBox ^^

First, let me state a couple of remarks, configuration explanations, and trials I already did:

1/ I first noticed this issue when making a try on the GOG version of "Ultima Worlds - Martian Dreams". I then made some experiments on my own old version of Martian Dreams using D-Feed. I also tried it on some of my favorite old games. The issue is alwas the same.

2/ More important, I am a near-blind (and more blind than near ^^) person, and use a video magnifier software (Lonar from the Dolphin comapny). This implies the following statements:

3/ I am still using Windows XP Pro, with the latest Service Pack

4/ The only way I managed to have the game corectly enlarged is by using the following setting:
- use DOSBox windowed mode, full-screen mode not being enlarged
- set the Render Method to "ddraw"
- disable the first level of video acceleration (cursor & bitmap). Without that, the game is drawn outside its windowd, and not enlarged at all.

Once all this is taken into account, the game is enlarged x4 as expected, and runs perfectly... until the mouse have to be used. And ther it is:

- When the mouse pointer enters the game windows, its look change to display a negative image of the standard Windows pointer, whatever it should display in the game. The game pointer never appears in the window.

- When I want to clic at the correct place in the game, it is interpreted in the game as either the mouse is outside the game, or the mouse is in the game, but not at the correct place.

==> The mouse is absolutly useless in any game I tried.

When trying to think about this, please have in mind the following: imagine the full windows screen divided into 4 rows and 4 colums, making a total of 16 cells. Now, take one of these cells, and enlarge it to fill the whole monitor, thus "hiding" the full real-screen. For navigation, this enlarged cell surround the mouse pointer, and thus follows it on its movements on the full hidden screen (I have to admit I nearly got sea-sick the first few days I used this software ^^). This may imply a divergence of mouse pointer coordinates in enlarged "cell" and full hidden screen that may explain the issue, but not resolce it...

As fot screenshots, I tried to make some of them, but it seems mouse cursor never appear in them.

If all of this doesn't seems very clear, please ask for more details.

Best regards